Neural crest cells are a population of vertebrate multipotent cells that migrate over long distances, form an impressive array of cell types, and are defective in diverse craniofacial abnormalities. Prenatal supplementation with folate, a cofactor in the methylation cycle, can reduce the incidence of craniofacial birth defects, yet unti recently any mechanistic impact of methylation on neural crest development was unknown. Recent data in the Gammill lab shows that the lysine methyltransferase NSD3 is required for neural crest cell migration. Based upon the cytoplasmic localization of both NSD3 and lysine methylated proteins in migratory neural crest cells, as well as increasing appreciation that 'histone' methyltransfserases methylate diverse non- histone proteins, this proposal postulates that NSD3-catalyzed methylation of non-histone proteins regulates neural crest cell migration. To investigate this possibility, the objective is to determine the importance of NSD3- mediated non-histone protein methylation during chick neural crest migration by identifying non-histone targets of NSD3 through two independent, complementary approaches in both directed and open-ended frameworks. This objective will be attained by: (1) screening NSD3-catalyzed methylation of candidate targets and arrayed proteins using an in vitro methyltranferase assay established by the candidate, (2) profiling NSD3-dependent non-histone protein methylation in C8161 melanoma cells using proteomics; and (3) determining the requirement for NSD3 target methylation during neural crest migration in vivo using chick transient genetic approaches. Achieving these aims will create a direct functional link between NSD3 non-histone methylation and neural crest cell migration, and will open exciting new avenues to explore in the treatment of aggressive cancers and the prevention of birth defects. Moreover, in completing this project, the candidate will acquire diverse expertise in proteomics, biochemistry, and developmental biology, giving him a broad knowledge base and a strong foundation in research. Mentoring by both a Sponsor and Co-Sponsor with extensive experience in these areas will ensure a successful completion of the research plan, as well as the implementation of a personalized training plan designed to prepare the candidate for a successful scientific career.